Tesla, TSLA & the Investment World: the Perpetual Investors' Roundtable

[Artful Dodger]

That the S/X would get the Roadster's 3-motor powertrain was mentioned by Elon before, we just didn't know the timing.

Ahaha no, that would have been me: Artful Dodger, Apr 5, 2019 |

"The refreSh (when it comes) will include the following:

• dual rear motors based on Roadster / SRPM driveline
• top speed > 180 mph / 300 kmh
• Quarter mile in < 10 sec @ 145 mph in 'Plaid' model
• Bonus feature: "FSD track mode":

Or here at TMC on June 6, 2019:

"The triple-motor package for S/X WILL NOT come out before its introduced in the 2020 Roadster. Why on earth would Tesla scoop their own halo car?"​

or from Sep 5, 2019 after Elon tweeted that a Model S was headed to Nürburgring:

"I'll make a prediction: if this Model S exceeds 300 kmh on Döttinger Höhe, then I predict its got the prototype 3-motor AWD powertrain (all SRPMs) from the Roadster 2."​

But today is the 1st time Elon has confirmed the intention to build the S/X/R2 with a common powertrain, although it has been obvious since the Semi reveal which way of the future is headed. And yes, you can expect the Roadster2 to be available at about the same time as the 3-motor S/X versions in 2020. Elon says "About a year".

The biggest unanswered question at this point is, when do S/X get a larger battery pack? It's unlikely the dual layer cell design of the Roadster's pack would work well in a sedan or SUV where foot/leg room is an important design goal. So how will they do it?

Will we see a transitional design continuing with the existing 100 KWh pack, or will they go to a larger pack based on new bty tech? I think we'll be able to make an informed call after "Battery and Powertrain Investor Day", sometime in 2020Q1.

Cheers!

 

[Mars ☰mperor]

BTW., the Laguna Seca record run with the Model S prototype:

Tesla on Twitter​

Was done with an amateur driver and on a pretty dusty, slippery track. There are at least 2 major slippages visible in the video which added at least another 1 second to the lap time, plus a professional driver could probably shave off another ~2 seconds. If you follow steering wheel movements and corrections in the video you can see 4-5 suboptimal over- and under- steering episodes.

So the 1:36.5 could possibly be improved to 1:34-ish times, maybe a bit better - matching performance with the best 2-door Porsche 911 Turbo S performance which is 1:33 ...

That's rather impressive racing performance!

Get Randy Pobst behind the steering wheel. He helped tune Model 3 track mode

 

[Artful Dodger]

I do hope Tesla has had a team working on the S/X refresh to restore it as the technology flagship of the fleet. And soon!

At a minimum, it should feature all of the tech and ergonomic upgrades of the 3 and a significantly greater range (400 mile minimum) than the 3 to differentiate it and to blow away any competition.

Furthermore, I think the S should incorporate design cues from the Roadster 2.0 to enhance its marketability. In particular, the fascia and headlights. This would require minimum retooling of presses and yet dramatically improve the styling without compromising the timeless elegance of the overall form. I think a simple interior refresh will not move the needle.

Lol, good call, especially for Apr 5th, 2019. You're gettin' good at this!

Cheers!

 

[KarenRei]

Dieselgate 2.0 continues:

Abgasskandal: Weitere Abschalteinrichtungen bei VW?

Earlier:

Knaller-Urteil im Diesel-Skandal: Auch VW Software Update ist manipuliert

 

[mikneyah]

I don’t think so, they will continue to move on the line up, and come back to it last whenever a legacy manufacturer does better then the model S 2012! The Tacan came close and that is only because they are copying the Model 3’s platform! They received the reports for the car and they brought one to get the details! Plus production hasn’t even started yet! There is talks and show-cases,but no real action yet. When customers get one in the hands we can compare, but for now it’s all talk!

 

[Fact Checking]

BTW., the Laguna Seca record run with the Model S prototype:

Tesla on Twitter

Was done with an amateur driver and on a pretty dusty, slippery track. There are at least 2 major slippages visible in the video which added at least another 1 second to the lap time, plus a professional driver could probably shave off another ~2 seconds. He also took good care of the tires and didn't risk the prototype: a more aggressive line with more rubber on the road would shave off seconds ...

So the 1:36.5 could possibly be improved to 1:34-ish times, maybe a bit better - matching performance with the best 2-door Porsche 911 Turbo S performance which is 1:33 ...

That's rather impressive racing performance!

As a comparison, here's a 10 seconds faster lap in a Porsche 911 GT3R racing car:

He is driving a much more aggressive line and the tires slip more despite the significantly higher downforce generated by the massive rear wing of a 911 GT3R:

 

[Mich]

BTW., the Laguna Seca record run with the Model S prototype:

Tesla on Twitter

Was done with an amateur driver and on a pretty dusty, slippery track. There are at least 2 major slippages visible in the video which added at least another 1 second to the lap time, plus a professional driver could probably shave off another ~2 seconds. He also took good care of the tires and didn't risk the prototype: a more aggressive line with more rubber on the road would shave off seconds ...

So the 1:36.5 could possibly be improved to 1:34-ish times, maybe a bit better - matching performance with the best 2-door Porsche 911 Turbo S performance which is 1:33 ...

That's rather impressive racing performance!

why does it have an emergency stop button?

 

[SpaceCash]

I'm in for 10 more, famalam

 

[jerry33]

Will a high performance S and X generate a lot of revenue for Tesla? Seems like a fairly niche market except for bragging rights.

A fairly niche market with big margins is nothing to sneeze at. And you don't want Tesla to take on Toyota's reputation ("Only old people drive one").

 

[Artful Dodger]

I now think P100D+ might be a clever "working title" you could interpret it literally as a P100D + "something".
That "something" could be "anything" or "lots of things".
But everyone is going to look at the title and jump to possibly incorrect assumptions, so we may soon know what the car can do, but we may not know the actual specs.

And the P85+ was ...?

 

[ReflexFunds]

View attachment 453546

I do wonder if the new 3 motor S&X and the Roadster will all be built on new combined body and general assembly lines.
It seems a capital and space efficient step to make a flexible line that can be used for Tesla's 3 lower volume vehicles and could also justify acceleration of the Roadster program. I think this could also reduce the production cost and price of Roadster and increase its potential volume. Perhaps P110D+ S&X starting at around $120-130k and then Roadster base starting at $150-170k.

The 3 motor S&X design adds credibility to LikeTeslaKim's source in early June. They said Tesla was testing a tri-motor design for both standard and performance variants with just over 400 miles range for Model S and nearing 400 miles for Model X - all with much lower weight and 250kW charging.

I guess if Tesla does move to a new design, it makes sense to start with the top performance variants as they start ramping up supply. As production gets to capacity they can also replace base S&X models with the new platform, but best for Elon not to mention this part at risk of osbourning. I'm not convinced it was a good idea for Elon to mention the new Plaid variant at all so far from production but it does help maintain Tesla's overall brand and hype.

 

[mongo]

Der SpaceX package will take the rear seat space in the Roadster. Doubtful that will be offered in S or X. We don't get big upgrades every year. We have been stuck on 100 kWh for a while.

The SpaceX pack also relies on surplus pack capacity to run the compressor (per Elon's tweet) so the half sized 100kWh likely isn't up to the task.

The torque vs. efficiency curves of most electric motors shows that a motor at half throttle is considerably more efficient than one at full throttle. So there should be some gain in output with an additional motor, even if the peak current remains about the same.

Aero loading is speed cubed (per mile is squared) so a 70 MPH car is 1/8 the aero and 1/2 the rolling resistance of a 140 MPH car. So you are already way down the power curve. Add in two rear motors and you're half again. And in a third front motor and even lower. So the losses of having the extra motor on may add to a shift to lower efficiency. If none are AC induction, they might be better off running the motor to avoid eddy losses.

We don't know if they'll run a stock Raven too. Would be a good idea for them to do so, even if only to get an internal benchmark - if then the time is good, shout about it, if not, iterate on the weaknesses without major changes.

If they run it, it will be known, and externally timed, and publicized (if slower). The plaid is out in a yearish. How much significant change could they do to the current version in that time? Automotive durability testing alone (for a meaningful change) will eat most of that time.

Tesla saw this from a mile away and started a plan to have good high speed racing results in 2015, the Roadster 2, which uses 3 motors with 3 different gearing ratios, which distributes power and allows better thrust vectoring as well.

The rear 2 motors need to have the same ratio.

3-motor configuration with three separate gearing ratios that distributes power output over a wide wheel RPM range from 0 to ~250 km/h with ~300 km/h top speed.

Nah, otherwise the car can't torque vector equally to the right and left. Rear motors need to be the same. (Unless NASCAR)

The 3-motor "Maximum Plaid" powertrain solves this problem at the root: by having a higher gearing a third motor Tesla is able to distribute power and shift up the maximum power output to a flat power curve like they did on the P90 chart, in addition to increasing maximum power as well.

Yeah, they can solve this problem by using two rear motors and giving each either a higher gear ratio or adjusting the motor windings for less operating back-EMF. The low end is always torque limited, the mid power limited, and the high end voltage limited. So double motors at a less advantageous low end fear ratio cancels out.

Pack power will be similarish (unless they did a little something there), so they are limited in total power mid band. Adjusting gearing and the new motor type helps extend that max power to the high end.

why does it have an emergency stop button?

Typical of prototype vehicles, especially with new drivetrain software. Emergency power kill.

 

[bhtooefr]

Tesla saw this from a mile away and started a plan to have good high speed racing results in 2015, the Roadster 2, which uses 3 motors with 3 different gearing ratios, which distributes power and allows better thrust vectoring as well. They also had two next-gen Model S prototypes available on a moment's notice, and they were on the Nürburgring within one week after the Taycan unveil.

Citation on the three different gear ratios? (That could cause awkward handling with the torque vectoring if left rear and right rear gear ratios differ, especially under maximum acceleration. I mean it could work, it'd just feel weird, and may require assistance from the power steering system to avoid torque steer.)

Existing P100s are faster 0-60 mph. The average speed for a lap of the 'ring will be about 100 mph. Its acceleration between 60 mph and 150+ mph that matters there.

That's why Tesla is switching to SRPM motors: no speed limits due to back EMF, no 2-speed gearbox needed, less weight, faster lap times. The previous generation AC induction motors are on their way out.

Cheers!

...hang on, my understanding is that the permanent magnets actually do contribute back EMF (but help smooth out the torque delivery and improved low speed torque, avoiding torque ripple issues. It's just that enough of the motor's torque comes from reluctance that the back EMF is low, and it responds well to field weakening?

Also worth noting: the inefficient European EVs seem to be standardizing on some form of permanent magnet motor all around, and this may be what's hurting their efficiency compared to dual motor Model 3 and Raven Model S/X - they have to field weaken (spending energy) at high speed no matter what, while Tesla can just shut the field off entirely (saving energy) on the motor they're not using.

 

[Fact Checking]

Citation on the three different gear ratios? (That could cause awkward handling with the torque vectoring if left rear and right rear gear ratios differ, especially under maximum acceleration. I mean it could work, it'd just feel weird, and may require assistance from the power steering system to avoid torque steer.)

No citation, I just assumed it to be so - but you are probably right that there are two gearing ratios - but the higher one could be pushed up, because there's plenty of power at lower speeds with three motors.

 

[Alphacrux]

I believe there's just two technological solutions that can result in good 4-door sedan Nürburgring results, given today's available li-ion cell chemistries and energy densities:

• 3-motor configuration with three separate gearing ratios that distributes power output over a wide wheel RPM range from 0 to ~250 km/h with ~300 km/h top speed.
  
• 2-speed transmission kludge and running the whole Nürburgring lap in second gear, with good power output in the Nürburgring's 70-250 km/h speed range.

Porsche went for the second option, Tesla chose the first one. Tesla's is obviously the better approach for a number of reasons, and they had two prototypes ready on call, which were on the Nürburgring one week after the Taycan unveil, which suggests that they were anticipating Porsche's PR approach.

Had Tesla gone on the Nürburgring first, Porsche might have picked some other track or other performance benchmark, with some other special property.

In an alternative universe, had the Taycan been able to beat the Model S in straight 0-60 mph performance, we'd probably not have seen a Taycan run on the Nürburgring so close to the unveil, but we'd be seing non-stop variants of acceleration comparisons in various professional and funny street settings, to drive home the message that Porsche is superior. We might have seen a Laguna Seca Taycan run and a PR emphasis on superior handling performance on slow, technical tracks like the Laguna Seca which require driver skill and a nimble car over a wide speed range, not just pure motor power. Porsche has near unlimited PR resources to shape the narrative...

When zero mass-advertising spending underdogs like Tesla are going up against the massive PR resources of the likes of the VW Group, who is the largest mass-advertising spender on the planet, pretty much the only valid approach is to first see what Porsche's PR narrative is, and then to react to it.

Agree. Musk would like 3 motor approach from “first principles” of optimizing motor torque combinations.

 

[lascavarian]

I’m guessing the bulk of the nice price bump is the recognition of the impact of EU carbon emissions standards and influx of capital that accrues to TSLA and is boosted by increasing production volumes.

Looks likeTesla’s balance sheet is likely to be going in a nice direction.

 

[MikeAtkinson]

First post,

After reading the forum for about a year, I've now placed orders for 103 shares. So now being an investor I've joined TMC and will post here occasionally.

My investment is long term 5-10 years and I'll probably increase it by about 20 shares in a few days.

 

[mongo]

Getting more OT...

...hang on, my understanding is that the permanent magnets actually do contribute back EMF (but help smooth out the torque delivery and improved low speed torque, avoiding torque ripple issues. It's just that enough of the motor's torque comes from reluctance that the back EMF is low, and it responds well to field weakening?

The magnets likely increase back-EMF, and an excited SR motor can produce back-EMF (hence regen). I think the magnets are there to allow Tesla to have 54 stator slots with the 6 pole SR rotor core (18 poles total). Increases power and reduces torque ripple.

Also worth noting: the inefficient European EVs seem to be standardizing on some form of permanent magnet motor all around, and this may be what's hurting their efficiency compared to dual motor Model 3 and Raven Model S/X - they have to field weaken (spending energy) at high speed no matter what, while Tesla can just shut the field off entirely (saving energy) on the motor they're not using.

Given the range difference, it seems more than motor efficiency. Tires, oils, bearings, weight, aero, electronics.
If the back EMF is less than pack voltage, then the losses would only be eddy currents in the housing. The small magnetic rotor motors Ixve worked with have a decent spin down time.

 

[Rohan]

So Tesla can roll out a "Nürburgring Option", which is a stock Raven Model S, with proper racing tires installed. Everything else is stock, plus Track Mode via OTA update.

Problem solved!

For $150k presumably?

 

[Stars aligned]

I’ve just another totally irresponsible thought...

Elon throws current generation of S/X under the bus. He needs space in the Fremont factory for GA .

Y coming soon?

(putting my helmet on and hiding behind a massive wall)